Renyi entropies and Fisher informations as measures of nonextensivity in a Tsallis setting

We study nonextensive statistical scenarios a la Tsallis with reference to Fisher's information and Renyi's entropy. A new way of evaluating Tsallis' generalized expectation values is examined within such a context, and is shown to lead to a much better Cramer-Rao bound than the customary procedure. A connection between the information measures of Fisher's and Renyi's is found. We show that Fisher's measure for translation families remains additive even in a non-extensive Tsallis setting. (C) 1998 Elsevier Science B.V. All rights reserved.